Yes and no. It's more like they're "recertified". It's pretty easy and non-invasive to replace the logic board, which can fix many problems that might warrant an RMA. I've also gotten refurbs back from Seagate and WDC RMA's that have new top covers on the drive (evidenced by a new, non-retail sticker, no old sticker underneath it). Presumably they're doing some inspection of the platters and heads before sending them out. These drives came with a 30day warranty and cleared SMART data. But I would argue that its fair to reset the SMART data after this kind of refurbishment/re-certification.

That being said, there are definitely some sketchy drive resellers on marketplaces like Amazon who just clear the smart data on old drives and sell them as refurbished, or even new.